tried proxmity check its ok
i also tried this method u post in sum other post
Try to dial *#*#7378423#*#* then go to service tests>>proximity switch and if you see ON always mean there is something wrong with the sensor...
but my sensor is ok ... it works fine
what else is there should i flash it ... do i need root to flash stock firmware with flash tool and where can i find stock roms for c6602 xperia z